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An Open Source JavaFX PDF Viewer
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/*
 * ===========================================
 * Java Pdf Extraction Decoding Access Library
 * ===========================================
 *
 * Project Info:  http://www.idrsolutions.com
 * Help section for developers at http://www.idrsolutions.com/support/
 *
 * (C) Copyright 1997-2015 IDRsolutions and Contributors.
 *
 * This file is part of JPedal/JPDF2HTML5
 *
     This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA


 *
 * ---------------
 * Vector_Double.java
 * ---------------
 */
package org.jpedal.utils.repositories;
import java.io.Serializable;

/**
 * Provides the functionality/convenience of a Vector for Doubles
 *
 * Much faster because not synchronized and no cast
 * Does not double in size each time
 */
public class Vector_Double implements Serializable
{
    
    //how much we resize each time - will be doubled up to 160
    int  increment_size = 1000;
    protected int  current_item;
    
    //current max size
    int  max_size = 250;
    
    //holds the data
    private double[] items = new double[max_size];
    
    private int checkPoint=-1;
    
    /**
     * used to store end of PDF components
     */
    public void resetToCheckpoint() {
        
        if(checkPoint!=-1) {
            current_item=checkPoint;
        }
        
        checkPoint=-1;
    }
    
    /**
     * used to rollback array to point
     */
    public void setCheckpoint() {
        if(checkPoint==-1) {
            checkPoint=current_item;
        }
    }
    
    protected static int incrementSize(int increment_size){
        
        if(increment_size<8000) {
            increment_size *= 4;
        } else if(increment_size<16000) {
            increment_size *= 2;
        } else {
            increment_size += 2000;
        }
        return increment_size;
    }
    
    //set size
    public Vector_Double( final int number )
    {
        max_size = number;
        items = new double[max_size];
    }
    
    /**
     * extract underlying data
     */
    public final double[] get()
    {
        return items;
    }
    
    /**
     * add an item
     */
    public final void addElement( final double value )
    {
        checkSize( current_item );
        items[current_item] = value;
        current_item++;
    }
    
    /**
     * remove element at
     */
    public final double elementAt( final int id )
    {
        if( id >= max_size ) {
            return 0d;
        } else {
            return items[id];
        }
    }
    ///////////////////////////////////
    /**
     * clear the array
     */
    public final void clear()
    {
        checkPoint = -1;
        //items = null;
        //holds the data
        //items = new double[max_size];
        if(current_item>0){
            for(int i=0;i0) {
            current_item--;
        }
        
        return ( items[current_item] );
    }
    
    
    /**
     * check the size of the array and increase if needed
     */
    private void checkSize( final int i )
    {
        if( i >= max_size )
        {
            final int old_size = max_size;
            max_size += increment_size;
            
            //allow for it not creating space
            if( max_size <= i ) {
                max_size = i +increment_size+ 2;
            }
            final double[] temp = items;
            items = new double[max_size];
            System.arraycopy( temp, 0, items, 0, old_size );
            
            //increase size increase for next time
            increment_size=incrementSize(increment_size);
        }
    }
    
    public void trim(){
        
        final double[] newItems = new double[current_item];
        
        System.arraycopy(items,0,newItems,0,current_item);
        
        items=newItems;
        max_size=current_item;
    }
}